JP4620015B2 - Plasma generating apparatus and work processing apparatus using the same - Google Patents

Description

  The present invention relates to a plasma generator capable of purifying or modifying the surface of a workpiece by irradiating plasma on a workpiece to be processed such as a substrate, and a workpiece processing apparatus using the plasma generator.

  For example, there is known a workpiece processing apparatus that irradiates a workpiece to be processed such as a semiconductor substrate with plasma and removes organic contaminants on the surface, surface modification, etching, thin film formation, or thin film removal. For example, in Patent Document 1, a plasma generating nozzle having concentric inner and outer electrodes is used, and a high-frequency pulse electric field is applied between both electrodes, thereby generating glow discharge instead of arc discharge. A high-density plasma is generated by rotating the processing gas from the gas supply source from the base end side to the free end side while swirling between the two conductors, and is covered by the nozzle attached to the free end. There has been disclosed a plasma processing apparatus capable of obtaining a high-density plasma under normal pressure by irradiating a processing work.

  Although the above-described conventional plasma generating nozzle has a shape suitable for generating plasma capable of generating high-density plasma under normal pressure, it is necessary to process a large-area workpiece or a plurality of workpieces collectively. There is a problem that it is not suitable. In other words, when the plasma reaches the desired irradiation position of the wide workpiece, the rate of the plasma being cooled and extinguished increases, and in order to perform plasma irradiation over the large area, the nozzle diameter is made large. Must. If so, there is a problem in that microwaves with a higher electric field must be generated, which increases costs and increases noise associated with plasma generation. There is also a problem that the glow discharge varies within the large-diameter nozzle, making control difficult.

On the other hand, Patent Document 2 discloses a plasma generation space formed by surrounding one side of the strip-like electrodes arranged in parallel to each other as an electric field application electrode and the other as a ground electrode. There is disclosed a plasma processing apparatus in which a processing gas is generated by supplying a processing gas into the plasma, and a workpiece is irradiated from a slit-shaped outlet formed in the longitudinal direction of the ground electrode. According to this prior art, plasma is radiated from the slit-shaped outlet, and plasma irradiation over a wide range becomes possible.
JP 2003-197397 A Japanese Unexamined Patent Publication No. 2004-6221

  In the above-described prior art disclosed in Patent Document 2, plasma processing gas may be irradiated relatively uniformly and over a wide range. However, since glow discharge is caused by parallel plate electrodes, a high voltage is required and expensive. In addition, there is a problem that the discharge is not stable. Also, local arc discharge is likely to occur, and in order to suppress it, it is necessary to cover at least one of the electrodes with a dielectric, and a higher voltage is required. Therefore, Patent Document 1 is superior in generating plasma.

  An object of the present invention is to provide a plasma that has a concentric inner electrode and outer electrode, and can perform uniform plasma irradiation on a wide workpiece even when using a low-cost and easy-to-control plasma generating nozzle. It is an object of the present invention to provide a generator and a work processing apparatus using the same.

The plasma generator of the present invention is a microwave generator that generates microwaves, a waveguide that propagates the microwaves, receives the microwaves, and generates plasma gas based on the energy of the microwaves. And a plasma generating device configured to include a plasma generating nozzle that is attached to the waveguide, and a plurality of the plasma generating nozzles are arranged and attached to the waveguide. Each plasma generating nozzle generates a glow discharge between the inner electrode and the outer electrode arranged concentrically to generate a plasma, and a processing gas is supplied between them, so that the plasma nozzle is normally supplied from an annular outlet. pressure is configured to emit plasma gas in said mounted to the distal end of each plasma generating nozzles, elongate the air outlet of the annular air outlet Characterized in that it comprises an adapter to convert.

According to the above configuration, in the plasma generating apparatus that can be used for workpiece processing such as substrate modification, the plasma generating nozzle is formed between the inner electrode and the outer electrode arranged concentrically. A discharge is generated to generate plasma, and a processing gas is supplied between them to form a shape suitable for plasma generation that emits plasma gas from an annular outlet under normal pressure. When a waveguide is used for propagation and a plurality of the plasma generating nozzles are arranged in the waveguide, the annular outlet is converted into a longitudinal outlet at the tip of each plasma generating nozzle. Attach the adapter.

  Therefore, when the plasma reaches the desired irradiation position of a wide workpiece directly from the outlet, the rate of the plasma being cooled and extinguished is high. However, it is difficult for the plasma in the path in the adapter to be cooled, and it is cooled only in a slight path from the opening portion near the irradiation position until it actually reaches the irradiation position. The rate at which the plasma disappears becomes small even if it is away from the center. Accordingly, even if a small-sized plasma generating nozzle that is easy to control at low cost is used without using an unnecessarily large plasma generating nozzle, uniform plasma irradiation can be performed on the wide workpiece.

Furthermore, when arranging a plurality of plasma generating nozzles to the waveguide, the adapter corresponding to each plasma generating nozzle, to attach to only tilted obliquely's predetermined angle with respect to the arrangement direction of the plasma generation nozzles, the It is possible to prevent the plasma blown out from the end portion in the longitudinal direction of the long outlet from colliding with each other between adjacent adapters, and to suppress the decrease in plasma density in the vicinity of the end portion.

Alternatively , the plasma generating nozzles are arranged in a plurality of rows in the waveguide in parallel with each other (if the plasma generating nozzles are mounted in a straight line on the plurality of waveguides parallel to each other, or the plasma is generated in one waveguide. When the generation nozzles are mounted in a plurality of rows), the plasma generation nozzles are arranged at intervals in the row direction when viewed from the direction orthogonal to the row direction (for example, two rows of plasma generation nozzles) In this case, they are arranged in a staggered pattern in plan view), and correspondingly, the adapter corresponding to each of the plasma generating nozzles is attached so that the longitudinal direction thereof is substantially parallel to the row direction, so that the longitudinal It is possible to prevent plasma blown out from the longitudinal end of the air outlet from colliding with each other between adjacent adapters, and reducing the plasma density in the vicinity of the end. It can be suppressed.

Or, when arranging a plurality of plasma generating nozzles to the waveguide, when arranged in a straight line, the adapter corresponding to the respective plasma generating nozzles, the longitudinal-shaped air outlet is, the straight line substantially parallel to and as the said straight line alternately between adjacent nozzles are sequence shifted in the orthogonal direction, for example, an adapter to form a longitudinal-shaped air outlet offset from the center of the annular air outlet, alternately By rotating it by 180 ° and attaching it to the plasma generating nozzle, it is possible to prevent the plasma blown out from the longitudinal end of the long blowout port from colliding with each other between adjacent adapters. A decrease in plasma density near the end can be suppressed.

Furthermore, the plasma generator of the present invention is characterized in that end portions in the longitudinal direction of adjacent adapters overlap each other when viewed from a direction orthogonal to the arrangement direction of the plasma generating nozzles.

According to said structure, the longitudinal direction edge part of the said longitudinal blower outlet in which a plasma density becomes relatively low is overlapped seeing from the direction orthogonal to the arrangement direction of the said plasma generation nozzle (overlapping). Thus , the plasma density can be made substantially uniform over the direction of arrangement of the plasma generating nozzles.

In the plasma generator of the present invention, the elongated blower outlet is formed such that the opening area is enlarged stepwise or continuously as it goes outward from the center of the blower outlet.

According to the above-described configuration, the momentum of the plasma (the pressure of the blowout, that is, the flow velocity (flow rate per unit time)) decreases from the center of the blowout port toward the outside in the longitudinal blowout port. Since the temperature also decreases, the longitudinal outlet is not simply formed to have a constant width, but the opening area is formed to be enlarged stepwise or continuously, so that the longitudinal outlet of the longitudinal outlet is increased. The amount of plasma to be blown out increases toward the outer side, and more uniform plasma irradiation can be performed over the entire length of the longitudinal blowout port.

  Furthermore, the workpiece processing apparatus of the present invention is characterized in that the plasma generating apparatus is provided with a conveying means for conveying the workpiece in a predetermined conveying direction.

  According to the above configuration, even with a small-sized plasma generating nozzle that is easy to control at low cost without using a large plasma generating nozzle, it is possible to perform uniform plasma irradiation on a wide workpiece. A work processing apparatus can be realized.

As described above, the plasma generator according to the present invention is a plasma generator that can be used for processing of a workpiece such as substrate modification, and the inner electrode and the outer electrode in which the plasma generating nozzles are arranged concentrically. Glow discharge is generated between them and plasma is generated, and a processing gas is supplied between them to form a shape suitable for generating plasma that emits plasma gas from the annular outlet under normal pressure. Further, when a waveguide is used for the propagation of microwaves and a plurality of the plasma generation nozzles are arranged in the waveguide, the annular blowout port is formed in a longitudinal shape at the tip of each plasma generation nozzle. Attach an adapter to convert the outlet.

  Therefore, even if a small-sized plasma generating nozzle that is easy to control at low cost is used without using an unnecessarily large plasma generating nozzle, uniform plasma irradiation can be performed on the wide workpiece.

  Furthermore, as described above, the workpiece processing apparatus of the present invention is provided with a transfer means for transferring the workpiece in a predetermined transfer direction in the plasma generator.

  Therefore, there is provided a workpiece processing apparatus capable of performing uniform plasma irradiation on a wide workpiece without using an excessively large plasma generating nozzle and using a small diameter plasma generating nozzle that is easy to control at low cost. Can be realized.

[Embodiment 1]
FIG. 1 is a perspective view showing an overall configuration of a work processing apparatus S according to an embodiment of the present invention. The workpiece processing apparatus S includes a plasma generation unit PU (plasma generation apparatus) that generates plasma and irradiates the workpiece W, which is an object to be processed, with the plasma, and a predetermined route that passes the workpiece W through the plasma irradiation region. It is comprised from the conveyance means C which conveys. FIG. 2 is a perspective view of the plasma generation unit PU having a different line-of-sight direction from FIG. 1, and FIG. 3 is a partially transparent side view. 1 to 3, the XX direction is the front-rear direction, the Y-Y direction is the left-right direction, the ZZ direction is the up-down direction, the -X direction is the front direction, the + X direction is the rear direction,- Y will be described as a left direction, + Y direction as a right direction, -Z direction as a downward direction, and + Z direction as an upward direction.

  The plasma generation unit PU is a unit capable of generating plasma at normal temperature and pressure using microwaves. In general, the waveguide 10 propagates microwaves, and one end side of the waveguide 10 ( Microwave generator 20 arranged on the left side to generate microwaves of a predetermined wavelength, plasma generator 30 provided on waveguide 10, and arranged on the other end side (right side) of waveguide 10 to reflect microwaves The sliding short 40 to be performed, the circulator 50 for separating the reflected microwaves from the microwaves emitted to the waveguide 10 so as not to return to the microwave generator 20, and the dummy load 60 for absorbing the reflected microwaves separated by the circulator 50. In addition, a stub tuner 70 for matching impedance between the waveguide 10 and the plasma generation nozzle 31 is provided. The conveying means C includes a conveying roller 80 that is rotationally driven by a driving means (not shown). In the present embodiment, an example in which a flat workpiece W is conveyed by the conveying means C is shown.

  The waveguide 10 is made of a nonmagnetic metal such as aluminum, has a long tubular shape with a rectangular cross section, and propagates the microwave generated by the microwave generator 20 toward the plasma generator 30 in the longitudinal direction thereof. Is. The waveguide 10 is composed of a connected body in which a plurality of divided waveguide pieces are connected to each other by flange portions, and the first conductor on which the microwave generator 20 is mounted in order from one end side. The wave tube piece 11, the second waveguide piece 12 to which the stub tuner 70 is assembled, and the third waveguide piece 13 provided with the plasma generator 30 are connected. A circulator 50 is interposed between the first waveguide piece 11 and the second waveguide piece 12, and a sliding short 40 is connected to the other end side of the third waveguide piece 13.

  The first waveguide piece 11, the second waveguide piece 12 and the third waveguide piece 13 are each formed in a rectangular tube shape using an upper plate, a lower plate and two side plates made of a metal flat plate, respectively. And flange plates are attached to both ends thereof. In addition, you may make it use the rectangular waveguide piece formed by extrusion molding, the bending process of a plate-shaped member, etc., or a non-dividing type | mold waveguide irrespective of the assembly of such a flat plate. Further, not only a nonmagnetic metal but also a waveguide can be constituted by various members having a waveguide action.

  The microwave generator 20 includes, for example, an apparatus main body portion 21 including a microwave generation source such as a magnetron that generates a microwave of 2.45 GHz, and the microwave generated by the apparatus main body portion 21 inside the waveguide 10. And a microwave transmission antenna 22 that emits light to the outside. In the plasma generation unit PU according to the present embodiment, for example, a continuously variable microwave generator 20 that can output microwave energy of 1 W to 3 kW is preferably used.

  As shown in FIG. 3, the microwave generation device 20 has a configuration in which a microwave transmission antenna 22 protrudes from the device main body 21, and is fixed in a mode of being placed on the first waveguide piece 11. Has been. Specifically, the apparatus main body 21 is placed on the upper surface plate 11U of the first waveguide piece 11, and the microwave transmitting antenna 22 is inside the first waveguide piece 11 through the through hole 111 formed in the upper surface plate 11U. The waveguide space 110 is fixed so as to protrude. With this configuration, the microwave of 2.45 GHz, for example, emitted from the microwave transmission antenna 22 is directed from one end side (left side) to the other end side (right side) by the waveguide 10. Propagated.

The plasma generating unit 30 includes a plurality of plasmas arranged on the lower surface plate 13B of the third waveguide piece 13 (a surface facing the workpiece to be processed) spaced apart from each other in the microwave propagation direction (left-right direction). A generation nozzle 31 is provided. The width of the plasma generation unit 30, that is, the arrangement width in the left-right direction of the eight plasma generation nozzles 31 is a width that substantially matches the size t in the width direction orthogonal to the conveying direction of the flat workpiece W. Thereby, the plasma processing can be performed on the entire surface of the workpiece W (the surface facing the lower surface plate 13B) while the workpiece W is being conveyed by the conveying roller 80. Note that it is desirable that the arrangement interval of the plasma generating nozzles 31 is determined according to the wavelength λ _{G of the} microwave propagating in the waveguide 10. For example, it is desirable to arrange the plasma generating nozzles 31 at a ½ pitch and a ¼ pitch of the wavelength λ _{G. When} a microwave of 2.45 GHz is used, since λ _G = 230 mm, 115 mm (λ _G / 2) The plasma generating nozzles 31 may be arranged at a pitch or 57.5 mm (λ _G / 4) pitch.

  The sliding short 40 is provided for optimizing the coupling state between the central conductor 32 provided in each plasma generation nozzle 31 and the microwave propagated inside the waveguide 10. The third wave guide piece 13 is connected to the right end of the third waveguide piece 13 so that the standing wave pattern can be adjusted by changing the microwave reflection position. Therefore, when a standing wave is not used, a dummy load having a radio wave absorption function is attached instead of the sliding short 40. The sliding short 40 includes, for example, a cylindrical reflection block inside, and the standing wave pattern in the waveguide 10 is optimized by sliding the reflection block in the left-right direction.

  The circulator 50 is composed of, for example, a waveguide-type three-port circulator with a built-in ferrite column. Of the microwaves once propagated toward the plasma generation unit 30, the plasma generation unit 30 returns without being consumed. The incoming reflected microwave is directed to the dummy load 60 without returning to the microwave generator 20. By arranging such a circulator 50, the microwave generator 20 is prevented from being overheated by the reflected microwave.

  The dummy load 60 is a water-cooled (or air-cooled) radio wave absorber that absorbs the reflected microwave and converts it into heat. The dummy load 60 is provided with a cooling water circulation port 61 for circulating cooling water therein so that heat generated by heat conversion of the reflected microwaves is exchanged with the cooling water. It has become.

  The stub tuner 70 is for impedance matching between the waveguide 10 and the plasma generation nozzle 31, and has three stub tuners arranged in series on the upper surface plate 12 U of the second waveguide piece 12 at a predetermined interval. Units 70A to 70C are provided. The three stub tuner units 70 </ b> A to 70 </ b> C have the same structure, and as shown in FIG. 3, the stub 71 projecting into the waveguide space 120 of the second waveguide piece 12 is moved up and down in the vertical direction. The power consumption by the conductor 32 is maximized, that is, the reflected microwave is minimized, so that plasma ignition is easily generated.

  The conveyance means C includes a plurality of conveyance rollers 80 arranged along a predetermined conveyance path, and the conveyance roller 80 is driven by a driving means (not shown), so that the workpiece W to be processed is generated by the plasma generation. It is conveyed via the section 30. Here, examples of the workpiece W to be processed include a flat substrate such as a plasma display panel and a semiconductor substrate, a circuit substrate on which electronic components are mounted, and the like. Also, parts or assembled parts that are not flat-shaped can be processed, and in this case, a belt conveyor or the like may be employed instead of the conveying roller.

  It should be noted that in this embodiment, an adapter 32 is attached to the tip of each plasma generating nozzle 31. 4 is an enlarged cross-sectional view showing the adapter 38 from the plasma generating nozzle 31, FIG. 5 is an exploded perspective view of the adapter 38, and FIG. 6 shows their attachment portions in the third waveguide piece 13. As shown in FIG. It is a perspective view which expands and shows. The plasma generating nozzle 31 includes a central conductor 32 (inner electrode), a nozzle body 33 (outer electrode), a nozzle holder 34, and a seal member 35.

  The center conductor 32 is made of a highly conductive metal such as copper, aluminum, or brass, and is made of a rod-like member having a diameter of about 1 to 5 mm. The upper end 321 side of the center conductor 32 is a lower plate 13B of the third waveguide piece 13. While vertically penetrating and projecting into the waveguide space 130 by a predetermined length (this projecting portion is referred to as a receiving antenna unit 320), the lower end 322 is substantially flush with the lower end edge 331 of the nozzle body 33. Is arranged. Microwave energy (microwave power) is applied to the central conductor 32 when the receiving antenna unit 320 receives the microwave propagating through the waveguide 10. The central conductor 32 is held by a seal member 35 at a substantially intermediate portion in the length direction.

  The nozzle body 33 is a cylindrical body made of a highly conductive metal and having a cylindrical space 332 that houses the central conductor 32. The nozzle holder 34 is also made of a highly conductive metal, and has a relatively large-diameter lower holding space 341 that holds the nozzle body 33 and a relatively small-diameter upper holding space 342 that holds the seal member 35. It is a state. On the other hand, the seal member 35 is made of a heat-resistant resin material such as Teflon (registered trademark) or an insulating member such as ceramic, and has a holding hole 351 for holding the central conductor 32 fixedly on its central axis. It consists of a body.

  The nozzle body 33 is provided in an annularly projecting manner from the upper side, an upper body part 33U fitted in the lower holding space 341 of the nozzle holder 34, an annular recess 33S for holding a gas seal ring 37 described later. A flange portion 33F and a lower body portion 33B protruding from the nozzle holder 34 are provided. In addition, a communication hole 333 for supplying a predetermined processing gas to the cylindrical space 332 is formed in the upper body portion 33U.

  The nozzle body 33 functions as an external conductor disposed around the central conductor 32. The central conductor 32 is a cylindrical space with a predetermined annular space H (insulation interval) secured around it. It is inserted on the central axis of 332. The nozzle body 33 has a nozzle holder such that the outer peripheral portion of the upper body portion 33U is in contact with the inner peripheral wall of the lower holding space 341 of the nozzle holder 34 and the upper end surface of the flange portion 33F is in contact with the lower end edge 343 of the nozzle holder 34. 34 is fitted. The nozzle body 33 is preferably attached to the nozzle holder 34 with a detachable fixing structure using, for example, a plunger or a set screw.

  The nozzle holder 34 includes an upper body portion 34U (corresponding approximately to the position of the upper holding space 342) and a lower surface plate 13B that are closely fitted in a through hole 131 formed in the lower surface plate 13B of the third waveguide piece 13. And a lower body portion 34B (substantially corresponding to the position of the lower holding space 341). On the lower surface plate 13B of the third waveguide piece 13, a cooling pipe 39 that radiates heat in contact with the lower body portion 34B is laid.

  Further, a gas supply hole 344 for supplying a processing gas to the annular space H is formed in the outer periphery of the lower body portion 34B. Although not shown, a pipe joint or the like for connecting a terminal portion of a gas supply pipe for supplying a predetermined processing gas is attached to the gas supply hole 344. The gas supply hole 344 and the communication hole 333 of the nozzle body 33 are set so that they are in communication with each other when the nozzle body 33 is fitted into the nozzle holder 34 at a fixed position. A gas seal ring 37 is interposed between the nozzle body 33 and the nozzle holder 34 in order to suppress gas leakage from the abutting portion between the gas supply hole 344 and the communication hole 333.

  A plurality of the gas supply holes 344 and the communication holes 333 may be perforated at equal intervals in the circumferential direction, and are not perforated in the radial direction toward the center. The gas may be perforated in the tangential direction of the outer peripheral surface of the cylindrical space 332 so as to swirl the gas. Further, the gas supply hole 344 and the communication hole 333 are not perpendicular to the central conductor 32, and may be formed obliquely from the upper end 321 side to the lower end 322 side in order to improve the flow of the processing gas. Good.

  The seal member 35 has a lower end edge 352 in contact with an upper end edge 334 of the nozzle body 33 and an upper end edge 353 in contact with an upper end locking portion 345 of the nozzle holder 34 in the upper holding space 342 of the nozzle holder 34. Is retained. That is, the upper holding space 342 is assembled so that the seal member 35 supporting the central conductor 32 is fitted and the lower end edge 352 of the nozzle body 33 is pressed by the upper end edge 334. is there.

  As a result of the plasma generation nozzle 31 being configured as described above, the nozzle body 33, the nozzle holder 34, and the third waveguide piece 13 (waveguide 10) are in a conductive state (the same potential), Since the central conductor 32 is supported by the insulating seal member 35, it is electrically insulated from these members. Therefore, when the microwave is received by the receiving antenna unit 320 of the central conductor 32 and the microwave power is supplied to the central conductor 32 in a state where the waveguide 10 is at the ground potential, the lower end 322 and the nozzle An electric field concentration portion is formed in the vicinity of the lower end edge 331 of the main body 33.

  In this state, when an oxygen-based processing gas such as oxygen gas or air is supplied from the gas supply hole 344 to the annular space H, the processing gas is excited by the microwave power and the lower end of the central conductor 32 is excited. Plasma (ionized gas) is generated near the portion 322. Although this plasma has an electron temperature of tens of thousands of degrees, the gas temperature is a reactive plasma that is close to the outside temperature (a plasma in which the electron temperature indicated by electrons is extremely high compared to the gas temperature indicated by neutral molecules). It is a plasma generated under normal pressure.

  The processing gas thus converted into plasma is radiated from the lower edge 331 of the nozzle body 33 as a plume by the gas flow provided from the gas supply hole 344. This plume contains radicals. For example, when an oxygen-based gas is used as a processing gas, oxygen radicals are generated, and a plume having an action of decomposing / removing organic matter, a resist removing action, and the like can be obtained. In the plasma generation unit PU according to the present embodiment, since a plurality of plasma generation nozzles 31 are arranged, it is possible to generate a line-shaped plume extending in the left-right direction.

  Incidentally, when an inert gas such as argon gas or nitrogen gas is used as the processing gas, the surface cleaning and surface modification of various substrates can be performed. Further, if a compound gas containing fluorine is used, the substrate surface can be modified to a water-repellent surface, and using a compound gas containing a hydrophilic group can modify the substrate surface to a hydrophilic surface. Furthermore, if a compound gas containing a metal element is used, a metal thin film layer can be formed on the substrate.

  The adapter 38 is generally covered with a mounting portion 381 into which the lower body portion 33B of the nozzle body 33 is fitted, a plasma chamber 382 extending horizontally from the tip of the mounting portion 381, and the plasma chamber 382. And a pair of slit plates 383 and 384. The plasma chamber 382 from the mounting portion 381 is formed by machining or casting, and is integrally formed. The slit plates 383 and 384 are formed by cutting or punching. The attachment portion 381 is formed thinly from the lower body portion 33B, whereby heat conduction is efficiently performed from the nozzle body 33 to the adapter 38.

  The attachment portion 381 is formed in a cylindrical shape, and when the lower body portion 33B is fitted into the cylinder, and the attachment screw 385 is screwed into the screw hole 3811 formed in the side portion, the tip 3851 thereof. Is fitted into a recess 33B1 formed on the outer peripheral surface of the lower body portion 33B, thereby preventing the removal. The slit plates 383 and 384 are attached to the bottom surface of the plasma chamber 382 by a plurality of countersunk screws 386.

  The plasma chamber 382 includes a pair of chamber portions 3821 and 3822 extending away from the lower end 3812 of the attachment portion 381, and a longitudinal groove 3823 that is recessed upwardly across the chamber portions 3821 and 3822. Are formed, and a substantially central portion of the concave groove 3823 is a large-diameter opening 3824 communicating with the inner peripheral portion of the mounting portion 381.

  By inserting the slit plates 383 and 384 into the concave grooves 3823 formed in this way, the space surrounded by the slit plates 383 and 384 and the chamber portions 3821 and 3822 becomes a chamber, and the cylinder of the nozzle body 33 is formed. The plasma-treated gas radiated from the space 332 propagates in the concave groove 3823 from the attachment portion 381 through the opening 3824, and is radiated in a strip shape from the outlet 387 between the slit plates 383 and 384. The width W0 of the outlet 387 is sufficiently larger than the diameter φ of the cylindrical space 332 of the nozzle body 33, for example, W0 = 70 mm for φ = 5 mm.

  Therefore, a glow discharge is generated between the central conductor 32 as the inner electrode and the nozzle body 33 as the outer electrode arranged concentrically to generate plasma, and a processing gas is supplied between them. Thus, in the plasma generating nozzle 31 that radiates plasma gas from the annular outlet under normal pressure, as shown in FIG. 7, when the plasma irradiation is performed on the desired irradiation position P of the wide workpiece W, the reference symbol L1 In the case of reaching directly from the outlet (cylindrical space 332 of the nozzle main body 33), the rate at which the plasma is cooled and disappears in most of the path L1 increases. On the other hand, by installing this adapter 38 that converts the annular outlet into a longitudinal outlet 387, the adapter 38 that becomes hot even in the same path length up to the irradiation position P can be obtained. In the passing path L21, the plasma is difficult to be cooled, and the cooling is performed only in the slight path L22 that exits from the opening portion nearest to the irradiation position P and actually reaches the irradiation position. Even if it is away from 33, the rate at which the plasma disappears is small. Accordingly, even if a small-sized plasma generating nozzle that is easy to control at low cost is used without using an unnecessarily large plasma generating nozzle, uniform plasma irradiation can be performed on the wide workpiece W.

  Further, as shown in FIG. 5 and FIG. 6 and the like, the adapter 38 has a longitudinal outlet 387 whose opening area is gradually increased as it goes outward (FIGS. 5 and 6). In the example of FIG. 6, the portion 3871 directly below the opening 3824 that directly receives the plasma flow from the cylindrical space 332 is formed to have a narrow width W1, for example 0.3 mm, and the other portion 3872 has a wide width W2, for example, 0. Formed to 5 mm).

  As shown in FIG. 8 (a), the shape of the outlet 387 may be formed such that the opening width of the longitudinal outlet is continuously enlarged as shown in FIG. 8 (a). The diameters of the spot openings arranged in the longitudinal direction may be sequentially enlarged and formed so that the number of the spot openings arranged in the longitudinal direction sequentially increases as shown in FIG. The opening area may be enlarged continuously or stepwise.

  With this configuration, the momentum of the plasma (the pressure of the blowing, that is, the flow velocity (flow rate per unit time)) decreases and the temperature also decreases in the longitudinal blowing port 387 toward the outside. Therefore, the longitudinal outlet 387 is not simply formed with a constant width, but the opening area is enlarged stepwise or continuously as described above, so that the longitudinal outlet 387 is formed. The amount of plasma that is blown out increases toward the outer side of 387, so that more uniform plasma irradiation can be performed on the wide workpiece W. The slit plates 383 and 384 may be formed integrally with each other, or a step for forming the portions 3871 and 3872 having different widths is provided on one side surface, and the other side surface may be flat. .

  Furthermore, in the adapter 38 having the elongated blowout port 387, when a plurality of plasma generating nozzles are attached to one adapter and the blowout ports communicate with each other, a collision occurs in the plasma flow from the adjacent plasma generating nozzles. In contrast to the occurrence of a portion where the plasma density is reduced, such an inconvenience can be eliminated by providing the adapter 38 in each of the plurality of plasma generating nozzles 31 as described above.

  Note that when one adapter is attached to a plurality of plasma generating nozzles, there is an advantage particularly in connection with attachment / detachment of the adapter, such as adjustment of the angular position of the adapter around the axis of the nozzle becomes unnecessary. For this reason, even if the longitudinal outlet 387 (opening portion by the slit plates 383 and 384) communicates, the inner chamber portions 3821 and 3822 are separated by a rectifying plate, and are adjacent as described above. When the collision of the plasma flow from the plasma generation nozzle can be suppressed, a plurality of plasma generation nozzles may be attached to one adapter.

Further, when the work processing apparatus S is configured by providing the plasma generating apparatus PU with the conveying means C, the microwave is propagated from the microwave generating apparatus 20 to the plasma generating nozzle 31 through the waveguide 10 and guided there. When the plurality of plasma generating nozzles 31 are attached to the wave tube in the longitudinal direction D2 of the waveguide 10 which is orthogonal to the conveying direction D1 of the workpiece W, as shown in an enlarged view in FIG. , the axis D3 of the adapter 38 is attached to only tilted swash's predetermined angle α with respect to (the longitudinal direction of the waveguide 10) arrangement direction of the plasma generation nozzle 31.

  By configuring in this way, it is possible to prevent the plasma blown from the longitudinal end portion of the longitudinal blowout port 387 from colliding with each other between the adjacent adapters 38. A decrease in plasma density in the vicinity of the portion can be suppressed.

  Furthermore, the longitudinal ends of the blowout ports 387 overlap with each other when viewed from the transport direction D1, so that the longitudinal ends of the longitudinal blowout ports 387 at which the plasma density becomes relatively low. The plasma density irradiated onto the workpiece W from the vicinity of the part can be made substantially uniform. The overlap amount W4 may be appropriately determined according to the length of the chamber portions 3821 and 3822, the shape of the blowout port 387, the gas flow rate, and the like.

  Next, an electrical configuration of the work processing apparatus S according to the present embodiment will be described. FIG. 9 is a block diagram showing a control system of the work processing apparatus S. This control system includes a CPU (central processing unit) 901 and an overall control unit 90 including its peripheral circuits, a microwave output control unit 91 including an output interface and a drive circuit, a gas flow rate control unit 92, and a conveyance control. Unit 93, a display means, an operation panel, and the like, an operation unit 95 for supplying a predetermined operation signal to the overall control unit 90, and sensor input units 96, 97 including an input interface, an analog / digital converter, and the like. And sensors 961, 971, a drive motor 931, and a flow rate control valve 923.

  The microwave output control unit 91 performs ON / OFF control and output intensity control of the microwave output from the microwave generator 20. The microwave output controller 91 generates the 2.45 GHz pulse signal and The operation control of the microwave generation by the apparatus main body 21 is performed.

  The gas flow rate control unit 92 controls the flow rate of the processing gas supplied to each plasma generation nozzle 31 of the plasma generation unit 30. Specifically, the opening degree of the flow rate control valve 923 provided in the gas supply pipe 922 connecting the processing gas supply source 921 such as a gas cylinder and each plasma generating nozzle 31 is adjusted.

  The conveyance control unit 93 controls the operation of the drive motor 931 that rotationally drives the conveyance roller 80, and controls the start / stop of conveyance of the workpiece W, the conveyance speed, and the like.

  The overall control unit 90 is responsible for overall operation control of the work processing apparatus S. The measurement result of the flow rate sensor 961 input from the sensor input unit 96 according to the operation signal given from the operation unit 95, the sensor The measurement result of the conveyance speed of the workpiece W by the speed sensor 971 input from the input unit 97 is monitored, and the microwave output control unit 91, the gas flow rate control unit 92, and the conveyance control unit 93 are controlled based on a predetermined sequence. Control the operation.

  Specifically, the CPU 901 starts conveying the workpiece W based on a control program stored in advance in the memory 902, guides the workpiece W to the plasma generation unit 30, and monitors the measurement result of the flow rate sensor 961. Then, while supplying a predetermined flow rate of processing gas to each plasma generation nozzle 31, a microwave-processed gas is generated by supplying microwave power, and the surface of the workpiece W is irradiated with the processing gas while conveying the workpiece W. Thereby, a plurality of works W are processed continuously.

  According to the work processing apparatus S described above, the work W is transported by the work transport means C, and plasma is generated from the adapter 38 at the tip of the plasma generating nozzle 31 attached to the waveguide 10 in an array. Since it is possible to radiate the gas to the workpiece W, it is possible to continuously perform plasma processing on a plurality of workpieces to be processed, and also to efficiently perform plasma processing on large-area workpieces. be able to. Therefore, it is possible to provide the work processing apparatus S or the plasma generation apparatus PU that is superior in plasma processing workability to various types of workpieces as compared with batch processing type work processing apparatuses. Moreover, since plasma can be generated at an external temperature and pressure, a vacuum chamber or the like is not required, and the equipment configuration can be simplified.

  In addition, the microwave generated from the microwave generator 20 is received by the receiving antenna unit 320 provided in each plasma generation nozzle 31, and the gas converted into plasma from each plasma generation nozzle 31 based on the energy of the microwave. Therefore, the transmission system of the energy held by the microwave to each plasma generating nozzle 31 can be simplified. Therefore, simplification of the device configuration, cost reduction, and the like can be achieved.

  Further, since the plasma generation unit 30 in which the plurality of plasma generation nozzles 31 are arranged in a line has a width that substantially matches the size t in the width direction orthogonal to the conveyance direction of the flat workpiece W, By simply passing the workpiece W through the plasma generating unit 30 only once by the conveying means C, the processing of the entire surface can be completed, and the plasma processing efficiency for the plate-shaped workpiece can be remarkably improved.

[Embodiment 2]
FIG. 10 is a diagram for explaining a nozzle and adapter arrangement in a workpiece processing apparatus according to another embodiment of the present invention. FIG. 10 is a view of the plasma generating unit 30 as viewed from the bottom side. It should be noted that in this embodiment, the plasma generating nozzles 31 are arranged in a plurality of rows in parallel with each other. In the example of FIG. 10, two waveguides 10A and 10B that are arranged in the transport direction D1 with a space between each other and extend in a direction orthogonal to the transport direction D1 (D2) are used. , 10B, the plasma generating nozzles 31 attached at intervals in the longitudinal direction D2 are arranged in a staggered manner in plan view. The adapter 38 is arranged in parallel with the longitudinal direction D2. Even with this configuration, it is possible to prevent the plasma blown from the longitudinal end portion of the longitudinal blowout port 387 from colliding with each other between the adjacent adapters 38, and in the vicinity of the end portion. It is possible to suppress a decrease in the plasma density.

Further, the adapter 38 has the longitudinal shape in which the plasma density is relatively low because the longitudinal end of the outlet 387 is overlapped (overlapped) when viewed from the transport direction D1. The plasma density irradiated onto the workpiece W from the vicinity of the end in the longitudinal direction of the blowout port 387 can be made substantially uniform. The plasma generation nozzles 31 need only be arranged in a plurality of rows at intervals in the transport direction D1 and extending in the orthogonal direction (D2). The plasma generation nozzles 31 may be arranged in a plurality of rows in one waveguide 10. May be.

[Embodiment 3]
FIG. 11 is a diagram for explaining a nozzle and adapter arrangement in a work processing apparatus according to still another embodiment of the present invention. FIG. 11 is also a view of the plasma generation unit 30 as viewed from the bottom side. It should be noted that in the present embodiment, in the waveguide 10 extending in the direction (D4) orthogonal to the transport direction D1, a plurality of the plasma generation nozzles 31 are mounted on a straight line D4 in the longitudinal direction. each corresponding adapter 38A, the longitudinal-shaped air outlet 387A is that parallel to the longitudinal direction of the waveguide 10, and shifted the in the conveying direction D1 alternately are array. In the example of FIG. 11, the adapter 38 </ b> A is configured such that an adapter 38 </ b> A having a longitudinal outlet 387 </ b> A that is shifted from the center (located on the D <b> 4) of the annular outlet (cylindrical space 332) The plasma generation nozzle 31 is attached by rotating 180 degrees.

  With this configuration, even if the plasma generating nozzle 31 is mounted on the straight line D4, the plasma blown out from the longitudinal end of the longitudinal blowout port 387A using the common adapter 38A. The adjacent adapters 38A can be prevented from colliding with each other, and a decrease in plasma density in the vicinity of the end can be suppressed. Furthermore, by using the offset arrangement and providing the overlap portion, the plasma density irradiated onto the workpiece W from the vicinity of the end portion in the longitudinal direction can be made substantially uniform.

The work processing apparatus S according to the embodiment of the present invention has been described above, but the present invention is not limited to this, and for example, the following embodiment can be taken.
(1) In the above-described embodiment, the transport unit C that transports the workpiece W is used as the moving unit. As the transport unit C, a mode in which the workpiece W is mounted on the upper surface of the transport roller 80 and transported is exemplified. In addition to this, for example, a form in which the work W is nipped between the upper and lower transport rollers and transported, a form in which the work is stored in a predetermined basket without using the transport roller, and the basket is transported by a line conveyor or the like, or a robot hand For example, the workpiece W may be gripped and conveyed to the plasma generation unit 30 by using a method such as that described above. Alternatively, the moving means may be configured to move the plasma generating nozzle 31 side. That is, the workpiece W and the plasma generation nozzle 31 may be relatively moved in a direction (X direction) intersecting the plasma irradiation direction (Z direction) and the arrangement direction (Y direction) of the plasma generation nozzles 31.
(2) In the above embodiment, a magnetron that generates a microwave of 2.45 GHz is illustrated as a microwave generation source. However, various high-frequency power sources other than the magnetron can be used, and a microwave having a wavelength different from 2.45 GHz. A wave may be used.

  A workpiece processing apparatus and a plasma generation apparatus according to the present invention include an etching processing apparatus and a film forming apparatus for a semiconductor substrate such as a semiconductor wafer, a glass substrate such as a plasma display panel and a cleaning processing apparatus for a printed board, and a sterilization process for medical equipment The present invention can be suitably applied to an apparatus, a protein decomposition apparatus, and the like.

It is a perspective view which shows the whole structure of the workpiece processing apparatus which concerns on this invention. FIG. 2 is a perspective view of a plasma generation unit with a different line-of-sight direction from FIG. 1. It is a partial see-through | perspective side view of a workpiece | work processing apparatus. It is sectional drawing which expands and shows an adapter from a plasma generation nozzle. It is a disassembled perspective view of the said adapter. It is a perspective view which expands and shows the attachment part from the said plasma generation nozzle to the waveguide of an adapter. It is sectional drawing which shows the function of an adapter typically. It is a figure for demonstrating the example of the other shape of the blower outlet of an adapter. It is a block diagram which shows the control system of a workpiece | work processing apparatus. It is a figure for demonstrating the nozzle and adapter arrangement | sequence in the workpiece processing apparatus which concerns on other forms of implementation of this invention. It is a figure for demonstrating the nozzle and adapter arrangement | sequence in the workpiece processing apparatus which concerns on further another form of implementation of this invention.

10, 10A, 10B Waveguide 20 Microwave generator 30 Plasma generating part 31 Plasma generating nozzle 32 Central conductor 320 Receiving antenna part 33 Nozzle body 332 Tubular space 34 Nozzle holder 344 Gas supply hole 38, 38A Adapter 381 Attachment part 382 Plasma chambers 3821, 3822 Chamber part 3823 Concave groove 3824 Opening part 383, 384 Slit plate 387, 387A Air outlet 40 Sliding short 50 Circulator 60 Dummy load 70 Stub tuner 80 Conveying roller 90 Overall controller 901 CPU
91 Microwave Output Control Unit 92 Gas Flow Rate Control Unit 921 Processing Gas Supply Source 922 Gas Supply Pipe 923 Flow Control Valve 93 Transfer Control Unit 931 Drive Motor 95 Operation Unit 96, 97 Sensor Input Unit S Work Processing Unit PU Plasma Generation Unit C Transfer Means W Work

Claims (6)

A microwave generating means for generating microwaves, a waveguide for propagating the microwave, and receives the microwave, plasma generation nozzle to release to generate plasma gas on the basis of the energy of the microwave In the plasma generator configured to include a plasma generator attached to the waveguide ,
A plurality of the plasma generating nozzles are arranged and attached to the waveguide, and each plasma generating nozzle generates a glow discharge between an inner electrode and an outer electrode arranged concentrically to generate plasma, By supplying the processing gas between them, it is configured to radiate plasma gas from the annular outlet under normal pressure,
The mounted to the distal end of each plasma generating nozzles, seen including an adapter for converting the annular air outlet in the longitudinal-shaped air outlet,
Each of the adapters is attached to a corresponding plasma generation nozzle inclined at a predetermined angle with respect to the arrangement direction of the plasma generation nozzles . A microwave generating means for generating a microwave; a waveguide for propagating the microwave; and a plasma generating nozzle for receiving the microwave, generating a plasma gas based on the energy of the microwave, and emitting the gas. In the plasma generator configured to include a plasma generator attached to the waveguide,
A plurality of the plasma generating nozzles are arranged and attached to the waveguide, and each plasma generating nozzle generates a glow discharge between an inner electrode and an outer electrode arranged concentrically to generate plasma, By supplying the processing gas between them, it is configured to radiate plasma gas from the annular outlet under normal pressure,
An adapter that is attached to the tip of each plasma generating nozzle and converts the annular outlet into a longitudinal outlet;
The plasma generating nozzles are arranged in a plurality of rows parallel to each other, and the plurality of rows are arranged at intervals in the row direction when viewed from a direction orthogonal to the row direction, and correspond to each plasma generating nozzle. adapter characteristics and to pulp plasma generating apparatus that the longitudinal direction is mounted in parallel the column direction and substantially. A microwave generating means for generating a microwave; a waveguide for propagating the microwave; and a plasma generating nozzle for receiving the microwave, generating a plasma gas based on the energy of the microwave, and emitting the gas. In the plasma generator configured to include a plasma generator attached to the waveguide,
A plurality of the plasma generating nozzles are arranged and attached to the waveguide, and each plasma generating nozzle generates a glow discharge between an inner electrode and an outer electrode arranged concentrically to generate plasma, By supplying the processing gas between them, it is configured to radiate plasma gas from the annular outlet under normal pressure,
An adapter that is attached to the tip of each plasma generating nozzle and converts the annular outlet into a longitudinal outlet;
The plasma generating nozzles are arranged on a straight line, and the corresponding adapters are arranged such that the long outlets are arranged substantially parallel to the straight line and alternately shifted in a direction orthogonal to the straight line. features and to Help plasma generating device. The plasma generating apparatus according to any one of claims 1 to 3 , wherein ends of adjacent adapters in the longitudinal direction overlap each other when viewed from a direction orthogonal to the arrangement direction of the plasma generating nozzles. The longitudinal-shaped air outlet, as the direction from the center of該吹spout outwardly to any one of claims 1 to 4, the opening area is characterized by being enlarged form stepwise or continuously The plasma generator described. 6. A workpiece processing apparatus, comprising: the plasma generating apparatus according to any one of claims 1 to 5 ; and a conveyance unit that conveys a workpiece in a predetermined conveyance direction.

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